• 한국잠사곤충학회지
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• 제42권2호
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• pp.67-72
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• 2000

Autotetraploid 'Sawonppong 26'was induced by dropping clochicine solution in growing point of Keomseolppong which is of high rootability and some agronomic charactelistics are as follows. Sawonppong 26 is a tetraploid of Keomseolppong with 56 of the chromosome number. Its fertlization percent was 59.4% and the germination percent of sank seed was normal. Sugar degree of mulberry fruit was 13.3% and total acidity was 0.69%. Single fruit weight of Sawonppong 26 was increased by 79%, as compared to that of Keomseolppong. Even though percent of survival of hard wood cutting was 94%, number of rootings was less and diameter of root was slender, it is expectedly a promising variety to be used for a breeding parent from the aspect of rootability.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2022년도 하계학술대회
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• pp.825-828
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• 2022

In this paper, we propose an efficient image size selection method for video-based point cloud compression. The current MPEG video-based point cloud compression reference encoding process configures a threshold on the size of images while converting point cloud data into images. Because the converted image is compressed and restored by the legacy video codec, the size of the image is one of the main components in influencing the compression efficiency. If the image size can be made smaller than the image size determined by the threshold, compression efficiency can be improved. Here, we studied how to improve the compression efficiency by selecting the best-fit image size generated during video-based point cloud compression. Experimental results show that the proposed method can reduce the encoding time by 6 percent without loss of coding performance compared to the test model 15.0 version of video-based point cloud encoder.

• 대한화장품학회지
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• 제10권1호
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• pp.8-12
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• 1984

Increasing the oil volume in the oil : water mixtures using isopropyl myristate, oleic acid as oils, the solubilities of methyl, propyl and butyl parabens and the MICs (minimum hibitory concentrations) to E. coli were increased. But in liquid paraffin, the solubility was reversed. The relation between MIC and solubility of parabens had constant factor of 0.7 as saturation fraction percent. The solubility of methyl paraben was crossed over in those of propyl and butyl parabens, when the oil volume was increased. When the oil was used over the cross-over point, methyl paraven was useful to preserve the systems, and below the cross-over point the more lipophilic propyl and/or butyl parabens were effective.

• 대한소아치과학회지
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• 제11권1호
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• pp.121-130
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• 1984

Childrens between the ages of 13 and 15 years, living in Seoul, were examined in order to determine the prevalence and severity of malocclusion in the permanent dentition. This survey encompassed 981 children and an individual chart was prepared for each subject recording an original HMAR score and classification of occlusion according to Angle. Also, subjective evaluation of "treatment needs" was carried out in 581 children. The results were as follows: 1. Of the 981 children in this survey, 12,1 percent showed excellent occlusion. (0 point) 2. The 14 percent of the children who had a score of 24 and above all appeared to belong to the "treatment highly desirable" or "treatment mandatory" category. 3. The incorporation of SAR (Supplementary Assessment Record) into the HMAR can provide more sensitive method for evaluating severity of malocclusion. 4. According to Angle's classification 77.4 percent of all malocclusion belonged to Class I, 1.3 percent to Class II, Division 1, 0.9 percent to Class II, Division 2, and 11.3 percent to Class III. 5. The mean HMAR score for Class I was significantly lower than for either Class II, Division 1 or Class III. (P < 0.05) 6. A close relationship was found between the degree of "treatment needs" and the value obtained by the HMAR scoring. (chi-square test, p < 0.05) The differences between the mean HMAR scores of the various subjectively defined categories were statistically significant. (P < 0.001)

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.94-96
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• 2003

Since 1995, MOCT(Ministry of Construction and Transportation) and KOWACO(Korea Water Resources Corporation) have established the National Groundwater Monitoring Network in South Korea and also MOE(Ministry of Environment) has operated Groundwater Quality Monitoring network. Until 2001, 202 monitoring stations by MOCT and 780 monitoring wells by MOE have been constructed, measured groundwater level and analyzed water samples. Groundwater quality analysis has been conducted two times a year during last 6 years for all monitoring wells. The quality data has about 15 components including pH, COD, Count of Coliform group, and etc.. Trend analysis has been peformed for 6 components(Coliform, pH, COD, NO$_3$-N, Cl and EC) of water quality which are analyzed more than 7 times for total monitoring wells. Two test methods have been used ; Sen's test and Mann-Kendall test. These trend tests have been done at the 0.05 significance level. By the result of Sen's test, Count of Coliform group has either upward or downward trends at 4.3 percent of the monitoring points. pH does at 5.6 percent, COD does at 8.6 percent, Nitrate-Nitrogen does at 13.2 percent, Chloride does at 13.4 percent, and. EC does at 11.6 percent of the monitoring points. The exact causes of the groundwater quality trends are difficult to specify. Notable downward trends in nitrate at many monitoring points may be the result of reduction on some contamination sources. Potential causes include diminished agricultural areas, improvements in sewage treatment and a decrease in atmospheric deposition. Increase in chloride at many monitoring points may be the result of increased non-point source pollution such as road salting and runoff from sprawling paved developments and suburbs.

• 환경영향평가
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• 제14권3호
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• pp.97-107
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• 2005

The purpose of this study is to develop a system, which estimates watershed pollutant loading rate through the combination of GIS and computational mode. Also, the applicability of this study was estimated by the application of the above system for Chuncheon City. The detailed results of these studies are as follows; The pollutant loading estimation system was developed for more convenient estimation of pollutant loading rate in watershed, and the system load was minimized by the separation of estimation module for point and non-point source. This system on the basis of GIS is very economical and efficient because it can be applied to other watershed with the watershed map. System modification is not needed. The pollutant loading estimation system for point source was developed to estimate the pollutant loading rate in watershed through the extraction of the proper data from all districts and yearly data and the execution of spatial analysis which is main function of GIS. From the verification result of spatial analysis, real watershed area and the administrative districtarea extracted by spatial analysis were $1,114,893,340.15m^2$ and $1,114,878,683.68m^2$, respectively. It shows that the spatial analysis results were very exact with only 0.001% error. The pollutant loading estimation system for non-point source was developed to calculate the pollutant loading rate through the overlaying of land-use and watershed map after the construction of new land-use map using the land register database with most exact land use classification. Application result for Chuncheon City shows that the proposed system results in one percent land use error while the statistical method results in five percent. More exact nonpoint source pollutant loading was estimated from this system.

• 한국학교보건학회지
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• 제12권2호
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• pp.339-356
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• 1999

The purpose of this study is to analyze the factors which influence the college student sex behavior. The results can be used as the basis to establish health polices and a health promotion program to reduce the risks of sexual behavior of college students. The study subjects were random selected from college students in Kyonggido. The 335 subjects were selected from 4 schools including three colleges and one university. The self-administered questionnaires were distributed to 350 students, 335 of which were analyzed (after excluding the 15 incomplete or inaccurate data). The study took place between December 7-19, 1998. Regarding the analysis method, the SPSS program was used. The relationship between social and demographic characteristics and relevant factors was identified through Chi-squared test. The major findings of the study were follows: 1. Of the 335 respondents, thirty seven percent of men and ten percent of women had already experienced sexual intercourse. Significantly more males had experienced sexual experience than women. The majority of students, living with both their parents had less sexually experience than that living without their parents. There were religious differences, that students who believed in buddhism had more sexual experience than christian or catholic students. Students who reported drinking alcohol frequently had more sexual experience than those who didn't and it was statistically significant (${\chi}^2=47.6$ df=4 p=0.000). 2. Sexual awareness was relatively low. High level group of sex knowledge were less sexual experience than middle or low level group (${\chi}^2=6.038$ df=2 p=0.049). Women were more sexually aware than men (${\chi}^2=20.814$ df=2 p=0.000). Groups who had sisters and brothers were more sexually aware than those who few sisters and brothers. 3. Sixty one percent of respondents said that chastity before marriage should be kept but twenty four percent of them felt that it was unnecessary. Opponents to chastity before marriage had more sex experience than those for. It was statistically significant (${\chi}^2=48.967$ df=2 p=0.000). Those who agreed with the questionnaire point 'Even if people are not married, if they love each other, they can have sexual intercourse.' had more sexual intercourse than those who didn't agree. Those who agreed with the questionnaire point 'Even though people doesn't like, they can still have sexual intercourse.' had more sexual intercourse than those who disagree. On this point, men were three times higher of the opinion than women. So we can see the difference in the perception between men and women. As a result of this study, sexual awareness influences sexual attitudes and sexual attitudes influence sexual awareness influences sexual activity includes poor knowledge and uninformed attitudes about sex. Therefore sex education is needed and it is very important to reestablish concepts about sex.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1377-1382
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• 2004

Flow fields in a half ducted propeller fan have been investigated by three-dimensional Reynolds-averaged Navier-Stokes (RANS) simulations and a vortex core identification technique. The simulation at the design operating condition shows that the tip vortex onset point is located at 30 percent tip chord of the suction surface on the blade tip. There is no interaction between the tip vortex and the adjacent blade, so that the tip vortex smoothly convects to the rotor exit. However, the high vorticity in the tip vortex causes the wake and the tip leakage flow to be twined around the tip vortex and to interact with the pressure surface of the adjacent blade. This flow behavior corresponds well with experimental results by Laser Doppler Velocimetry. On the contrary, the simulation at the low-flowrate operating condition shows that the tip vortex onset point is located at the 60 percent tip chord of the suction surface. In contrast to the design operating condition, the tip vortex grows almost tangential direction, and impinges directly on the pressure surface of the adjacent blade.

• 한국초등수학교육학회지
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• 제20권1호
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• pp.35-53
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• 2016

이 연구는 우리나라 초등학교 예비 수학교사들의 수학 교수 효능감이 어느 정도인지를 분석한 것이다. 강문봉과 김정하가 개발한 효능감 측정 도구를 이용하여 분석하였으며, 3개 교육대학의 수학교육과 2학년과 4학년 164명을 대상으로 분석하였다. 분석 결과 예비 초등 수학교사들의 수학 교수 효능감은 약간 긍정적인 수준에 있으며, 남녀 또는 고등학교 때의 이수 계열이나 대학교의 학년 사이에 통계적으로 유의한 차이는 없었다. 그러나 지역간에 어느 정도 유의한 차이가 드러났으며, 특히 사회문화적 영향에 대한 신념은 다른 요인에 비해 상당히 낮게 나타났다.

• Journal of Nutrition and Health
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• 제31권9호
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• pp.1498-1507
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• 1998

The purposes of this study were to : a) examine the current foodservice management practices of twenty-one seniors centers in charge of hoke-delivered meal programs, b) evaluate the attitudes of one hundred and ten recipients of meal service program, and c) provide feedback for the efficient and effective foodservice management for the elderly. Statistical data analysis was completed using the SAS package program for descriptive analysis, T-test, and ANOVA. The results of quantitative analysis indicated that the costs of meals, containers and special foods were mostly dependent on the support from local government(Seoul city). The centers where the volunteers were over seventy five p ercent of the workers were frtty-eight percent and sixty-seven percent of the subjects in food preparation and food delivery to the homebound clients, respectively. Meal preparation and food purchasing were mainly practiced by social welfare worker. Standardized recipes were not developed and meal preparation was controlled under the cook' and volunteers' experiences. The survey results of recipients who participated the home-delivered meals program showed that the mean of meal satisfaction score was rated over three point five in the five-point scale. There were significant differences between dependent variables(volunteer's kindness, plate waste, menu variety) and independent variables(sex, receiving periods and family type of the subjects). (Korean J Nutrition 31(9) : 1498-1507, 1998)